Serum prothrombin-free

The clear serum of this example is an amber liquid free from prothrombin, thrombin, fibrinogen and fibrin. It contains profibrinolysin and is excellently suited to further purification by salt precipitation fractionation, as given below. 

Major components of blood plasma are complex proteins such as globulins, serum albumin, fibrinogen, prothrombin and lipoproteins. In addition, urea, cholesterol, glucose, sodium chloride and various organic acids are also present. Numerous other components, usually present in trace quantities, include hormones, vitamins, free amino acids, foreign ions and elements. 

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